Converting Calories to watts or pace

[TheGuvnor]

Hi All,

Ex-Rower here from Ireland.

I'm wondering if there is a calculator for converting calories burned back to pace or watts?

I'm having a discussion on Facebook and my opponent has said:

'I pulled it n average 2.6 cals per pull which is about 156 cals per minute so that is 2340 cals in 15 minutes. I never checked meters when I did that.'

I'm trying to explain to him that this is not physically possible but he is adamant about it.

All help much appreciated.

[Citroen]

Maths is here: http://eodg.atm.ox.ac.uk/user/dudhia/ro ... #section11
A bit of limbering up with Excel (or a calculator, sheet of A4 and a pencil) should give you what you want.

BTW, measuring in watts with spm is sane, measuring in pace with spm is also sane. Measuring in calories is insane (as you'll see from the maths).

[Cyclist2]

C2 has calculators to convert watts, pace, calories VO2 max. Here is the link: https://www.concept2.com/indoor-rowers/ ... calculator.

There are explanations of the math they use, shortcomings, estimates, etc. on each page.

[jamesg]

Assuming the machine operates as expected and is a recent C2, the kCal readout in PM memory after stopping is in kCal/h. But it's easy to think it's the total. The rolling total is shown only during work.

If someone pulls at 593 W for just one stroke, the PM readout will show 593 x 0.86 x 4 + 300 = 2340 kCal/h, where 0.86 is the W-kCal conversion (1kW = 860kCal), 25% (4) is our estimated mechanical efficiency and 300 is a C2 add-on.

To show 2340 kCal as an average in PM memory after work, average Wattage must be 593, so no joke.

Give the man his money, but not for arithmetic; especially if he did row at almost 600W for 15 minutes and not just 15 strokes.

[Citroen]

Give the man his money, but not for arithmetic; especially if he did row at almost 600W for 15 minutes and not just 15 strokes.

600W is 5383m in 15 mins at 1:23.6.

That's a 5:34.4 2K (en-route to that 5383m) which is a world class performance (better than Josh Dunkley-Smith's 5:35.8 Heavyweight 2K record @ 592.6W).

That's probably all the OP was wanting.

[TheGuvnor]

Thanks Guys!

The chap said his split was 1m35 now for 15 minutes that is very decent rowing.

It's just the 2.6 calories burned per stroke and he was rating 60 strokes per minute for 15 minutes and burned 2340 kcals in 15mins or 9360 in an hour.

He's ok this chap but I just can't workout how they got their figures so wrong.

Even if he was working at 2340 kcals per hour that would still be quite something!

[TheGuvnor]

Thanks Citroen - I have a pen and a pad - wish me luck lol!

Maths is here: http://eodg.atm.ox.ac.uk/user/dudhia/ro ... #section11
A bit of limbering up with Excel (or a calculator, sheet of A4 and a pencil) should give you what you want.

BTW, measuring in watts with spm is sane, measuring in pace with spm is also sane. Measuring in calories is insane (as you'll see from the maths).

[TheGuvnor]

Thanks Cyclist2 - been here and unless I am missing something there is no calculator for working out watts or pace based on calories is there?

C2 has calculators to convert watts, pace, calories VO2 max. Here is the link: https://www.concept2.com/indoor-rowers/ ... calculator.

There are explanations of the math they use, shortcomings, estimates, etc. on each page.

[TheGuvnor]

Thanks James!

I was just browsing a FB post and this popped up in the discussion so I said wait a minute 156 calories a minute for 15 minutes.

We all know he has his figures muddled up but I'm just confused as to how he could have it so wrong - he thinks he burned 2340 calories in 15 minutes not the hourly average - 60 strokes a minute and 2.6 calories per stroke...I know...

BTW he does know his split was 1m35 so he averaged 1m35 over the 15 minutes which is a very good average tbf.

Assuming the machine operates as expected and is a recent C2, the kCal readout in PM memory after stopping is in kCal/h. But it's easy to think it's the total. The rolling total is shown only during work.

If someone pulls at 593 W for just one stroke, the PM readout will show 593 x 0.86 x 4 + 300 = 2340 kCal/h, where 0.86 is the W-kCal conversion (1kW = 860kCal), 25% (4) is our estimated mechanical efficiency and 300 is a C2 add-on.

To show 2340 kCal as an average in PM memory after work, average Wattage must be 593, so no joke.

Give the man his money, but not for arithmetic; especially if he did row at almost 600W for 15 minutes and not just 15 strokes.

[TheGuvnor]

If my maths is correct he would be averaging 2628W or 51.1s per 500m for 15m to burn 2340 calories.

I just don't know how anyone could think they burned 2340 calories in 15 minutes.

[hjs]

If my maths is correct he would be averaging 2628W or 51.1s per 500m for 15m to burn 2340 calories.

I just don't know how anyone could think they burned 2340 calories in 15 minutes.

Say he would do that over 5 hours, or a firm grand tour stage, that would be x4 x 5 making it a nice 46.800 kcal over 5 hours, this while pro cyclist “only” roughly 6.000 kcal needs to keep them going.

This would burn 5 kg of pure fat, 9.000 kcal per kg.

[Ombrax]

51.1s per 500m for 15m

Not shabby at all - in fact it sounds to me like the guy's a cyborg.

[jamesg]

2340 kcals in 15mins or 9360 in an hour.

Which is what was not done and never will be. I've found it very uncomfortable to think about calories, since I read that that Scott and his men on the way to the South Pole burnt 6000 kCal per day. Each.

Starting Nov 1st 1911 Scott's team pulled their sleds about 1400 km and to 3000m altitude; and almost as far back before dying there on March 29th 1912.